Effects of high pressure processing on the interaction of α-lactalbumin and pelargonidin-3-glucoside

Abstract The effects of high pressure processing on the binding interactions of α-lactalbumin and pelargonidin-3-glucoside were studied using the fluorescence quenching, molecular dynamic simulation and molecular docking analysis. The results of fluorescence quenching indicated that the high pressure processing significantly increased the quenching constants of α-lactalbumin at pH 7.4 and pH 8.0. The accessible fraction at pH 8.0 was significantly increased, while the fractions at pH 6.0 and pH 7.4 were increased without significant difference. Molecular dynamic simulation and docking results demonstrated that the coil structures and locations, and the residues structures in the binding site of α-lactalbumin were affected, the binding site was the typical binding site of calcium ion and not changed during the processing. The dissociation constant of histidine residues was in the range of 6.13 to 6.83, the charge on the residues increased when pH value increased, affected the binding interactions and caused the quenching constant difference.